1. Technical Field
Aspects of this document relate generally to pool skimmer systems.
2. Background Art
Most swimming pools have a skimming device connected to the suction of a pump to draw water from the pool at or very near the pool surface. These devices usually include a basket or strainer to separate larger debris such as leaves and other floating particles. Water drawn from the skimmer can be connected to the suction of a pump that is connected to a typical swimming pool filter system and returned back to the pool in one or more ordinary ways well known in the art. It is common to connect the suction of several pumps to a skimmer in order to enhance skimming action. There are skimmers commonly called Venturi skimmers, equipped with a pressure jet located to entrain water within the skimmer and eject it back to the pool through a relatively short unobstructed conduit. This method produces a significant flow increase through the skimmer resulting in improved surface debris entrapment.
Typically, the pump suction connected to a skimmer is also connected to one or more other drains within the pool. This provides protection to the skimmer basket should it become blocked by debris. The suction is simply diverted to the other drain thereby protecting the skimmer basket from deformation or bursting.
In the case of connecting pump suction to a skimmer only, the basket will usually fail when totally blocked by debris, resulting in the expense and labor of cleaning the system of debris and replacement of the damaged basket. In the case of a Venturi skimmer, when the debris basket becomes blocked, the Venturi return line becomes a point of suction that can be very dangerous to a bather. This is particularly true when the suction of a pump is also connected to a Venturi type skimmer as the flow through the Venturi return is reversed when the basket becomes full or otherwise blocked due to the suction of the separately attached pump.
There are skimming devices that provide air relief in an effort to solve the forgoing problems. U.S. Pat. No. 5,830,350 to Price describes a skimmer basket that has a central perforated pylon extending from the basket bottom to above the basket rim. The pylon consumes a portion of the basket capacity and is difficult to manufacture. U.S. Pat. No. 7,300,576 to Blake describes a conventional Venturi skimmer with an external tube running from the upper interior of the main skimmer body to a location below the skimmer basket in the main skimmer body. This method results in a necessarily small tube on the exterior of the skimmer which is very difficult to clean (due to the 90 degree turns involved) and costly to manufacture. Furthermore, the chance of damaging the skimmer during the construction process is increased due to its exterior nature.